The present invention relates to a cleaning method of a sugarcane harvester in which with, a main blower is usually arranged in a lower region of the sugarcane harvester an inclined and upwardly directed cleaning air stream oriented to a discharge hood is produced, and second deviating blower deviates an air stream so that the foreign parts to be separated are guided through the discharge hood.
The present invention also deals with a sugarcane harvester, in particular performing the inventive method, which is provided with rotor dividers, a cutter disk device, an inclined conveyor, a comminuting device for the stalks, a discharge conveyor, a discharge hood and a cleaning chamber with a main blower and a deviating blower for producing and guiding a cleaning air stream. It has been conventional to inflame the field before harvesting of the sugarcane to burn the leaves and tips. The subsequent harvesting is performed either by hand or by a correspondingly designed sugarcane harvester. The comminuted stalks are identified as billets. For separating the foreign particles from the billets in the residues of the leaves and tips, the sugarcane harvesters are provided with two blowers. For this purpose, axial and radial blowers are utilized, and both blowers have the same construction or a combination is used. By means of the axial blower it is possible to provide a suction pull. However, the disadvantage of it is that also the billets can be sucked in. The axial blower is provided exclusively for sucking out the foreign particles with the air stream and supplying the same to the discharge hood. Such a harvester is disclosed for example in the German patent document DE 34 29 204 C2 and DE 33 34 968 A1. A main blower mounted in the lower part of this sugarcane harvester is a radial blower. The blowing out pipes of the main blower are inclined in direction of the subsequently discharge hood. Because of their greater weight, the billets fall on the discharge conveyor, while the foreign particles are taken by the air stream or aspirated by the air stream of the axial blower and fall through the opening of the discharge hood onto the field.
The above described harvesters have been substantially proven in the practice. However, it is expected that in the near future stricter environmental laws will be accepted which will forbid worldwide flaming before the harvesting, so that only so called "green sugarcane" can be harvested, whereby the fraction of the foreign particles to be separated relative to the sugarcane itself will extremely increase. Therefore with the obtained power of a sugarcane harvester of the known type will lead to poor cleaning output. The reason is that the cleaning spaces or cleaning chambers are too small and the time for the separation of the increased quantity of the foreign particles is too low. Moreover, no axial blower can be utilized any longer because it should be taken into consideration that, the billets are aspirated and shattered more intense, and therefore the losses are too high. Furthermore, the harvested product correspondingly is guided through a disproportionally narrow structural space in an extremely short time.